Patients with whiplash syndrome have problems especially in that a strain is placed on the neck and they are not able to sleep peacefully with a normal pillow. Patent Document 1 proposes a cervical spine correcting tool of a pillow shape with elasticity formed with a concave part for placing a correcting part at the middle of a top surface, where a space is provided at the middle of the bottom surface, and the middle of the bottom surface lowers by the load on the top surface when the correcting part is placed on the top surface thereby narrowing the concave part. The cervical spine correcting tool has an effect of treating whiplash syndrome by restricting the orientation of the neck to a constant.
[Patent Document 1] Japanese Laid-Open Patent Publication No. 2001-178755